Heart diseases including angina pectoris, myocardial infarction and cardiac failure, and cerebrovascular disease including cerebral infarction, cerebral hemorrhage and subarachnoid hemorrhage are closely related to hypertension, and ranked second and third as the causes of death of the Japanese, respectively. Further, according to National Livelihood Survey (for fiscal 1998) by the Ministry of Health, Labor and Welfare of Japan, those patients going to clinics or hospitals for treatment of high blood pressure amount to 64 per a population of 1,000, with topping the list of the causes of disease. In other countries, like Japan, these heart diseases and cerebrovascular diseases rank high in the causes of death and the number of sufferers of hypertension continues to increase.
Typical medical means for hypertensives include administration of drugs such as diuretics, sympatholytics agents, vasodilators or angiotensin converting enzyme inhibitors, which are principally applied to severely suffering patients. On the other hand, since general treatments aimed at improving lifestyle habits, such as dietary therapy, exercise therapy, drinking and smoking control, are applicable widely to mildly to severely hypertensive patients, significance of such general treatments is highly acknowledged now. Above all, the improvement in dietary habits is said to be of great importance, and there are many foods traditionally known as having an antihypertensive action. Further, food-derived antihypertensive agents have long been pursued, with the result that a multitude of active substances having an antihypertensive action have so far been separated and identified.
The applicant has studied various food materials to search for any ingredient having an antihypertensive action and found out that chlorogenic acids can show an excellent antihypertensive action (cf. Japanese published unexamined patent applications 2002-53464 and 2002-87977). However, chlorogenic acids have a problem of producing bitterness or astringency when added to foods and drinks, especially beverages. Such bitterness or astringency is so severe particularly in beverages that those beverages are difficult to take in continuously.
Accordingly, the present invention provides a beverage comprising a high concentration of chlorogenic acid(s) which has an antihypertensive action and favorably high storage stability, making it possible to drink even everyday with good flavor.